Add commas between contributors

package.json

@@ -46,29 +46,29 @@
     {
       "name": "Tom Demeyer",
       "email": "[email protected]"
-    }
+    },
     {
       "name": "Rutger van Willigen"
-    }
+    },
     {
       "name": "Jelle Herold"
-    }
+    },
     {
       "name": "Petra Dreiskämper"
-    }
+    },
     {
       "name": "Menno den Engelse"
-    }
+    },
     {
       "name": "Taco van Dijk"
-    }
+    },
     {
       "name": "Lodewijk Loos"
-    }
+    },
     {
       "name": "Job Spierings",
       "email": "[email protected]"
-    }
+    },
     {
       "name": "Rein van 't Veer"
     }